Examples of different variable types in java

InstanceVariables.java

package variableTypes;

public class InstanceVariables {
	
		public int mCost;//manage outside class access using access modifiers.
	
		//Default public constructor
		public InstanceVariables(){}
		
		public InstanceVariables(int profit){
			int cost = profit + 30;//cost is a local variable which is initialized during declaration only.
			mCost = cost;
			System.out.println("local variable cost => "+ cost);
		}
		
		public void getDogDetails() {
			int age = 0;//Local variable must be initialized before use
			age = age + 7;
			System.out.println("Dog age is : " + age);
			
			//Local variable
			for(int i=0;i<3;i++){ //i is a local variable
				System.out.println("printing local variable. i => "+i);
			}			
		}

		public static void main(String args[]) {
			InstanceVariables test = new InstanceVariables();
			test.getDogDetails();
			//instance variables are accessed using InstanceName.variableName.
			System.out.println("Accessing instance variable without setting its value. So it prints default value. mcost => " + test.mCost);
			
			InstanceVariables test2 = new InstanceVariables(100);
			System.out.println("Accessing instance variable after setting its value through construcot initialization. mcost => " + test2.mCost);
			//Here test and test2 are local variables.
			
		}
}

LocalVariables.java

package variableTypes;

public class LocalVariables {
	
	//Default public constructor
	public LocalVariables(){}
	
	public LocalVariables(int profit){
		int cost = profit + 30;//cost is a local variable which is initialized during declaration only.
		System.out.println("local variable cost => "+ cost);
	}
	
	public void getDogDetails() {
		int age = 0;//Local variable must be initialized before use
		age = age + 7;
		System.out.println("Dog age is : " + age);
		
		//Local variable
		for(int i=0;i<3;i++){ //i is a local variable
			System.out.println("printing local variable. i => "+i);
		}			
	}

	public static void main(String args[]) {
		LocalVariables test = new LocalVariables();
		test.getDogDetails();
		
		LocalVariables test2 = new LocalVariables(100);	
		//Here test and test2 are local variables.
	}

}

StaticVariables.java

package variableTypes;

public class StaticVariables {
	
	//fixing cost of the dog as 30$ irrespective of dog type.
	public static final int mCost = 30;	 
	 	 	
	public static void main(String args[]) {		 		
		//static variables are accessed using className.staticVariableName.
		System.out.println("Accessing static variable directly with class name. mcost => " + StaticVariables.mCost);		
	}
}